Bassetlaw District Council has granted planning permission, described in trade press coverage as “irrevocable,” for a 400 MW battery energy storage system proposed by developer Field at High Marnham, Nottinghamshire — on the site of a former coal-fired power station. Construction is expected to begin in 2028 and take roughly two years. No storage duration in MWh has been disclosed for the project in the coverage available, so its total energy capacity, as distinct from its 400 MW power rating, isn’t yet public.
I could not confirm exactly what makes this specific permission “irrevocable” in planning-law terms — UK planning approvals aren’t typically labeled that way as a formal legal category, and the phrase may simply reflect that the permission has passed its legal challenge window or is unconditional in a way that trade press is characterizing loosely. Worth checking Bassetlaw’s own planning committee records if that detail matters for publication.
High Marnham Power Station operated as a coal-fired plant from 1959 to 2003, burning around 10,000 tonnes of coal a day at its peak and employing workers who lost their jobs when it closed. Its chimneys came down in 2004, its boiler house in 2006, and its five cooling towers in 2012. Part of the site’s former rail spur was repurposed in 2009 as Network Rail’s High Marnham Test Track. Bassetlaw’s local planning policy has separately designated the wider High Marnham site as an “Energy Hub” allocation, and the old cooling-tower footprint already hosts an unrelated, much smaller hydrogen project — a 200 kg-per-day hydrogen production unit developed by JG Pears Property Ltd, using an electric heater to crack ammonia into hydrogen and nitrogen for use on construction sites, approved by the council in 2024. Field’s battery project is a separate development from that hydrogen unit, but both illustrate how the former coal site has become a testbed for multiple energy-transition uses since the plant’s demolition.
Once operational, High Marnham will use Field’s in-house “Gaia” platform, an AI-driven system that automates a battery site’s participation in intraday, wholesale, and balancing markets to capture trading value on a daily basis. Gaia first launched at Field’s site in Oldham, Greater Manchester, in December 2024.
High Marnham’s 400 MW rating makes it larger, by power capacity, than any of Field’s currently financed UK projects — a portfolio of three sites (Whitebirk at 25 MW, Holmston at 50 MW, and Drum Farm at 50 MW, all two-hour-duration systems) financed via a £42 million non-recourse loan from Rabobank and ING. But Field has other large projects in its wider pipeline: its Rigifa battery project in Scotland (200 MW/3,600 MWh) has also recently secured planning approval, and five Field projects were selected for Ofgem’s long-duration electricity storage support scheme, together totaling 1.6 GW and 26.8 GWh of capacity — so while High Marnham is a significant addition to Field’s UK book, whether it becomes the company’s single largest UK project overall will depend on its still-undisclosed energy capacity and on how quickly those other large-scale projects move toward construction.
Field is a British battery storage developer and operator active across Europe, backed by infrastructure investor CVC DIF; its UK operating entity is registered as Virmati Energy Ltd, trading as Field.
